package zky410;

import java.util.Scanner;

public class zkk {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String next = in.next();
        try {
            int N = Integer.parseInt(next);
            if(N>12 ||N<=0){
                System.out.println("O");
            }else{
                StringBuilder str = new StringBuilder();
                find(1,N,str,true);
                System.out.println(str.toString());
            }
        }catch (Exception e){
            System.out.println("N");
        }
    }
    public static void find(int i,int N, StringBuilder str,boolean flag){
        if(i>N){
            return;
        }
        find(i+1,N,str,false);
        if(flag){
            str.append("R");
        }else{
            str.append("G");
        }
        find(i+1,N,str,true);

    }
}
